Kotlin Compiler 1.4

The 1.4 version of the Kotlin compiler is already enabled in Android Studio with Compose, so you can try it out on your projects. We're seeing a 4 to 5 time speed up compared to the current front end. 60% to 80% of your Kotlin compilation time is spent in the front end. Having a factor of 4 or 5 improvement on that is going to be really, really good for Kotlin compile time. And also for Kotlin in the editor, we hope.